Perineal dermatitis (including diaper dermatitis) has been defined as contact dermatitis in the perineal area, including the perineum, buttocks, and the perianal, coccyx and upper/inner thigh regions (Brown D. S., Sears M., Perineal Dermatitis: A Conceptual Framework, Ostomy/Wound Management 1993, 39 (7), 20-25). The physical signs of perineal dermatitis may include one or a combination of erythema, swelling, oozing, vesiculation, crusting and scaling, with the possibility of excoriation, thickening and hyper-pigmentation over time (Brown).
Perineal dermatitis is believed to be caused by the prolonged contact of the skin with body waste such as urine and feces. Although the exact component(s) of body waste responsible for perineal dermatitis has not been identified, factors that are suspected of causing perineal dermatitis include ammonia, moisture, bacteria, urine pH, and Candida albicans. Because these various suspected factors have different properties and require different therapies, one of the most effective methods of treating perineal dermatitis has been the application of a topical protective barrier agent between the skin and the body waste.
Several topically applied barrier agents are or have been commercially available. Exemplary agents are listed, for example, in U.S. Pat. No. 5,043,155 issued to Puchalski et al. on Aug. 27, 1991. Such agents are typically in the form of powders, lotions, creams and ointments and may contain a variety of ingredients. For example, the agents listed in the U.S. Pat. No. 5,043,155 may contain calcium undecylenate, talc, starch, calcium carbonate, petrolatum, cod liver oil, vitamins A and D, lanolin, balsam, silicone, including dimethicone, zinc oxide, bismuth subnitrate, benzalkonium chloride, methylbenzethonium chloride, and protein hydrolysate containing amino acids.
Skin protectant agents, for example, dimethicone, are also disclosed in the Federal Register, Vol. 48, No. 32, Feb. 15, 1983, pages 6820-6833 (proposed rule of the U.S. Dept. of Health and Human Services, Federal Food and Drug Administration). Skin protectant drug products for over-the-counter human use, such as diaper rash products, which may include, for example, dimethicone, are discussed in the Federal Register, Vol. 55, No. 119, Jun. 20, 1990, pages 25204-25232 (proposed rule of the U.S. Dept. of Health & Human Services, Federal Food and Drug Administration).
Known personal cleansing compositions may contain very small amounts of anti-foaming agents, e.g., silicone oils. Such anti-foaming agents are typically employed in amounts of less than about 0.01 weight % of the composition. Such minute amounts do not provide any significant benefits to the skin.
Barrier agents for protection against perineal dermatitis may be applied by sprinkling the agent onto the skin, by massaging the material into the skin with the hands, or via a wiping material. Wiping materials are typically used for cleansing while changing an infant diaper or adult incontinence article. Disposable wipes are pre-moistened, disposable towelettes. The towelette is typically a nonwoven formed of various combinations of cellulosic fibers, synthetic polymeric fibers such as polyester, polypropylene and the like, and binders. The nonwoven is generally moistened with a composition containing water (94% or more) and various combinations of other ingredients including moistening agents or humectants, emollients, surfactants, emulsifiers, anti-microbial agents, skin protectants, pH-adjusting agents, fragrances, powders and the like. Several exemplary ingredients that may be used in disposable baby wipes are disclosed in the above referenced U.S. Pat. No. 5,043,155.
As recognized in U.S. Pat. No. 5,043,155, many wipes have historically required the separate application of a barrier agent. More recently, wipes that are said to cleanse and carry a skin protectant onto the skin have become commercially available. An example of such wipes are Baby Fresh With Ultra Guard.RTM. baby wipes. The Baby Fresh.RTM. baby wipes are marketed with a patent marking of U.S. Pat. No. 4,904,524 (issued to Yoh on Feb. 27, 1990).
It is desirable that, in addition to providing effective cleansing, the wipe itself leave a substantive, highly protective residue on the skin. In order to provide maximum protection against perineal dermatitis, it is desirable that compositions used in wipe products be highly homogeneous. Thus, the components should be homogeneously distributed in the composition so as to provide consistent application of the composition to, or distribution of the composition in, wipe substrates, the skin, or other surfaces. It is also desirable for the composition to rapidly de-emulsify upon application to the skin, and to resist re-emulsification after such application.
The residue left by a wipe should also have several properties. The residue should protect the skin against irritants accompanying body waste, yet should not significantly reduce transepidermal moisture loss, i.e., the skin should be allowed to breathe even in the presence of the residue (thus, the residue is non-occlusive). Occlusive barrier agents tend to cause excess hydration of the skin, which renders the skin more susceptible to irritation or infection. Moreover, it is desirable for the residue to provide easier cleansing of the perineal region.
In addition, it is often desirable that the residue and the wipe provide a favorable esthetic, particularly tactile, perception to the user of the wipe (the user of the wipe may be a wearer of an incontinence article or a care-giver to such wearer). For example, the residue and the wipe should not be excessively greasy, oily, or tacky and should provide an impression of softness or silkiness. The residue should have a sufficiently low coefficient of friction to minimize the risk of skin abrasion or red-marking, and to improve the spreadability of other protective barrier agents that may be applied. The wipe should provide an impression of sufficient wetness and should feel soft and non-irritating to the user.
Finally, the composition used in the disposable wipe should not negatively impact the physical properties of the nonwoven substrate so as to excessively reduce its utility for the intended application. In addition, the composition should inhibit the growth of a broad range of bacteria, fungi and other microorganisms.
While the art has provided several compositions having various levels of utility in personal cleansing or treatment for the prevention of perineal dermatitis, the art has not provided the desirable characteristics of such compositions in the manner or to the extent of the present invention.
It is therefore an object of the present invention to provide a composition that is useful for personal cleansing and for reducing the risk of perineal dermatitis. More particularly, it is an object to provide such compositions that are highly homogeneous and which rapidly de-emulsify upon application to skin and that do not tend to re-emulsify, so as to ensure a substantially uniform, yet non-occlusive, layer of substantive protective barrier agent on the skin. It is a further object of the present invention to provide such compositions which are esthetically pleasing to the user. Another object of the invention is to provide such compositions that have a coefficient of friction that is sufficiently low so as to minimize the risk of skin abrasion or red-marking, to provide easier subsequent cleansing of the skin, and to improve the spreadability of other protective barrier agents that may be applied.
It is another object of the invention to provide a method of making such compositions.
Yet another object of the invention is to provide wipe products containing the composition, more particularly a wipe product that provides effective cleansing and that also leaves a substantive, highly protective residue on the skin. Another object of the invention is to provide a wipe product that is soft and non-irritating to the user.